FXUS63 KOAX 040403 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1003 PM CST Tue Dec 3 2024 .KEY MESSAGES... - Strong winds gusting 35-45 mph are expected tomorrow afternoon and evening behind a cold front that will dive south across our area. - Very cold temperatures are expected Wednesday night through Thursday night. The coldest temperatures will be early Thursday morning, with wind chills potentially dipping below zero for a few hours. - Warmer temperatures are expected this weekend, with many warming up into the 50s by Sunday afternoon. && .DISCUSSION... Issued at 221 PM CST Tue Dec 3 2024 Today through Thursday Night... High pressure will remain in place across much of the central Plains and Midwest today, bringing clear skies and dry conditions to our area. Tonight, a potent shortwave trough will dive south-southeast into the upper Midwest from south-central Canada. Although the associated surface low will pass well to our northeast, a cold front will push north to south across our area tomorrow during the day. Cloud cover will increase considerably behind the front, with isolated sprinkles/flurries heading into tomorrow afternoon/evening (10-15 percent chance). A few may see a dusting of snow by tomorrow night (5 percent chance), but accumulating, measurable snow is not expected. The bigger impact with this system will be strong winds tomorrow afternoon and evening. The strongest winds will be north of US-30, with peak wind gusts of 40-45 mph expected. Slightly weaker winds gusting 30-40 mph will be possible south of US-30. Post-frontal temperatures will also be significantly colder. Temperatures Thursday morning will range from the 10s in southeast Nebraska and southwest Iowa to the single digits in northeast Nebraska and west-central Iowa. This in conjunction with wind gusts 20-25 mph will likely result in the coldest wind chills so far of the season. Locations south of I-80 will see wind chills Thursday morning near zero degrees. Portions of northeast Nebraska and west-central Iowa may see wind chills as low as -10 degrees. Friday through Monday... With surface high pressure and southerly surface winds dominating much of the central and eastern CONUS heading into this upcoming weekend, we will see the return of warmer temperatures back into our area. Friday highs are expected to be in the low to mid 40s, with temperatures climbing into the 50s both Saturday and Sunday afternoons. The blocking ridge out west looks to break down, at least temporarily, by the end of this weekend heading into the beginning of next week. Various weak upper-level disturbances may traverse the central CONUS over the weekend. The only impacts these will bring will be periods of increased upper- level clouds. No precipitation is expected at this time. Medium range guidance is increasingly confident that a trough will amplify and dive southeast into the central CONUS Sunday night into Monday. Additionally, a sub-tropical jet will extend from central Mexico, north-northeast into the mid-Mississippi River valley. To further complicate the upper-level flow, medium range deterministic guidance resolves multiple low-amplitude perturbation embedded in the larger scale upper-level flow over much of the CONUS. In general, the left-exit region of the sub- tropical jet coupled with forcing for ascent downstream the approaching trough may favor surface cyclogenesis somewhere in the central CONUS. The exact location and timing of this surface low continues to be shrouded by substantial uncertainty resulting from model to model, and run to run variability in its meteorological details. While a few ensemble members of the GEFS and ECMFW Ens bring snow into our area, the vast majority of models keep us dry, as moisture return to the central Plains may not happen quick enough before upper-level forcing for ascent moves to the east of our region. Nonetheless, the potential is non-zero (20-35 percent chance) of light snow showers developing across our area sometime Monday or Tuesday, particularly if an aforementioned low-amplitude disturbance can provide a temporary enhancement to forcing for ascent. Precipitation chances will increase if subsequent model runs are more aggressive with moisture return into the central Plains, or if the upper-level disturbance trends slower in its movement to the east across the US. It cannot be stressed enough though, there is substantial uncertainty with the forecast for the beginning of next week, so please check back for forecast updates throughout the week. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1003 PM CST Tue Dec 3 2024 VFR conditions favored through the period, though there is about a 50/50 shot of seeing some brief MVFR ceilings and OFK Wednesday afternoon, with much smaller chances at OMA and LNK. Winds will remain light overnight, out of the northwest at OFK and southwest becoming northwest at OMA and LNK. Expect some low level wind shear with northwest winds around 1500 ft at 40 kts. Surface gusts will then pick up during the day, topping out in the 30 to 40 kt range before coming down a bit in the evening. Finally, can't completely rule out some flurries/sprinkles in northeast Nebraska, including OFK in the afternoon, but not expecting any impacts at this time. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...Wind Advisory from 9 AM to 9 PM CST Wednesday for NEZ011-012- 015>018-031>034-043>045. IA...Wind Advisory from 9 AM to 9 PM CST Wednesday for IAZ043-055- 056. && $$ DISCUSSION...Darrah AVIATION...CA